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Proventricular dilatation disease is a lethal disease of psittacine birds. In this study, we characterized the local cellular immune response in the brain, proventriculus, and small intestine of 27 cockatiels ( Nymphicus hollandicus) experimentally infected with parrot bornavirus 2 (PaBV-2). Perivascular cuffs in the brain were composed of CD3+ T-lymphocytes and Iba1+ macrophages/microglia in most cockatiels (n = 26). In the ganglia of the proventriculus, CD3+ T-lymphocytes (n = 17) and Iba1+ macrophages (n = 13) prevailed. The ganglia of the small intestine had a more homogeneous distribution of these leukocytes, including PAX5+ B-lymphocytes (n = 9), CD3+ T-lymphocytes (n = 8), and Iba1+ macrophages (n = 8). Our results indicate that perivascular cuffs in the brain and the inflammatory infiltrate in the proventriculus of PaBV-2-infected cockatiels is predominately composed of T-lymphocytes, while the inflammatory infiltrates in the ganglia of the small intestine are characterized by a mixed infiltrate composed of T-lymphocytes, B-lymphocytes, and macrophages.

Amphisbenians are limbless reptiles that belong to the order Squamata. Due to their fossorial and secrevie habits, little is known about their morphology, ecology and pathological conditions that may affect them. In this manuscript, we present a brief guide for identification of normal structures as well as traumatic injuries on radiography and necropsy of Amphisbaena alba. From April to September 2019, three cases of A. alba with suspected trauma were referred to the Veterinary Hospital of the Federal University of Paraíba (UFPB). In the clinical evaluation, traumatic injuries were observed, and support therapy was instituted, but they did not resist and died shortly after. Bone fractures and organ ruptures, in addition to specific structures of this species were identified on radiography. A systematic necropsy was performed of all amphisbaenians in order to evaluate external and internal structures, not only to identify lesions but also to investigate the morphological aspects of amphisbenids. Macroscopically, multiple organ fractures and ruptures observed in radiographs were confirmed, in addition to the presence of the cestodes Semenoviella amphisbaenae in the large intestine. Histologically, it was possible to identify normal characteristics and microscopic lesions in the tissues. This is the first study to incorporate morphological, clinical, and pathological aspects of A. alba. This manuscript brings essential information for wildlife veterinarians and pathologists who may have to treat or perform a necropsy on these unique reptiles. RESUMO: Anfisbenas são répteis desprovidos de membros que pertencem a ordem Squamata. Devido a seus hábitos fossoriais e reclusos, pouco se conhece sobre sua morfologia, ecologia e condições patológicas que possam afetá-las. Neste artigo, um guia sucinto para a necropsia, identificação de tecidos e órgãos e lesões encontradas em Amphisbaena alba, é apresentado. Durante março e dezembro de 2019, três casos de A. alba com suspeita de trauma foram encaminhados ao Hospital Veterinário da Universidade Federal da Paraíba. Na avaliação clínica foram observadas lesões traumáticas e instituído um suporte terapêutico, porém não resistiram e morreram em seguida. Foram realizadas projeções radiográficas onde identificaram fraturas e ruptura de órgãos, além de identificar estruturas específicas dessa espécie. Uma avaliação completa de estruturas externas e internas foi conduzida para investigar aspectos morfológicos dos anfisbenídeos. Macroscopicamente foram confirmadas múltiplas fraturas e rupturas de órgãos observadas anteriormente nas radiografias, além disso evidenciou no intestino grosso presença de parasitos anoplocéfalos denominados Semenoviella amphisbaenae. Na histologia foi possível identificar características normais e lesões microscópicas nos tecidos. Esse é o primeiro estudo a incorporar aspectos morfológicos, clínicos e patológicos de A. alba. Esse manuscrito traz informações essenciais para clínicos e patologistas de animais selvagens que podem se deparar com casos clínicos ou de necropsia de Amphisbaena alba.

A 4-mo-old northern red-shouldered macaw ( Diopsittaca nobilis) was admitted to the veterinary hospital of the Arruda Câmara Zoo, in the State of Paraiba, Brazil, for investigation of an orbital mass. Given rapid progression and lack of response to treatment, the bird was euthanized, and an autopsy was performed. Histologically, the mass consisted of a retrobulbar invasive tumor characterized by tubular and rosette-like structures, with interspersed heteroplastic tissues, such as aggregates of neuroglial cells and islands of hyaline cartilage. The tumor was immunopositive for pancytokeratin, GFAP, NSE, and S100. These findings were compatible with an ocular teratoid medulloepithelioma, a neoplasm best described in humans but also reported rarely in young cockatiels and African Grey parrots.

Rabies is a viral zoonotic disease present in two thirds of all countries, and causes the death of one person every 10 minutes (~70,000 deaths/year). The reservoirs of the Rabies Virus (RABV) are bats and canids, and it has also been found in other animals, including Cerdocyon thous (crab-eating fox) and Pseudalopex vetulus (hoary fox). Here we used Next Generation Sequencing (NGS), phylogenetic, and in vitro/in vivo analyses, to characterized the genome of a new subtype of RABV circulating in foxes of the Northeastern region of Brazil. We verified that although these variants were similar to existing strains from wild canids and domestic canines from Brazil, the samples contained escape mutants, suggesting that it was a heterogeneous virus population. In all, we used several molecular techniques to characterize a new RABV strain circulating in wild-foxes in Northeastern Brazil, and verified still manifested its notorious pathogenic characteristics.

Proventricular dilatation disease (PDD) is a lethal and important disease of captive psittacine birds, and affects a wide range of species, including endangered ones, and lacks an effective treatment. This report describes PDD in three blue-and-gold macaws (Ara ararauna) in southern Brazil. All three macaws originated from the same aviary and presented similar clinical signs including anorexia, apathy, emaciation and prostration. At necropsy, one of the macaws presented an enlarged proventriculus. Histologically, lymphoplasmacytic infiltrates was observed in the ganglia and nerves of the esophagus, crop, proventriculus, ventriculus, heart, adrenal glands, and adrenal medulla of all three cases. Two macaws had meningoencephalomyelitis and one had myocarditis. Immunohistochemistry identified PaBV antigen in the brain, proventricular, ventricular ganglia, and epicardial ganglia, and cardiomyocytes of all three macaws. RESUMO: A doença da dilatação proventricular (PDD) e uma importante e fatal doença de psitacídeos de cativeiro, que afeta uma grande variedade de espécies e não tem um tratamento efetivo até o momento. Este relato descreve PDD em três araras canindé (Ara ararauna) no sul do Brasil. Todas as três araras eram provenientes do mesmo criatório e apresentaram sinais clínicos semelhantes incluindo anorexia, apatia, emaciação e prostração. Na necropsia, uma das araras apresentou proventrículo dilatado. No exame histopatológico, infiltrados linfoplasmacitários foram observados em gânglios e nervos do esôfago, inglúvio, proventrículo, moela, coração, glândulas adrenais e rins de todos os casos. Adicionalmente, meningoencefalomielite foi observada em duas araras e miocardite em uma. A imuno-histoquímica identificou antígenos de PaBV no encéfalo, coração, proventrículo e moela de todos os casos.

Clostridium chauvoei causes blackleg in cattle. The disease has been reported worldwide, and although it can be prevented by vaccination, sporadic cases and occasional outbreaks still occur. We describe a case of blackleg in a 2-y-old, pregnant Gyr cow with in utero transmission to the fetus. The cow had characteristic gross and microscopic lesions of blackleg including widespread necrohemorrhagic and emphysematous skeletal and myocardial myositis, and fibrinous pericarditis. Her uterus contained a near-term, markedly emphysematous fetus with skeletal muscle and myocardial lesions similar to those seen in the dam. Histopathology of dam and fetal tissues revealed numerous gram-positive bacilli, many of them with sub-terminal spores, in multiple tissues. These bacilli were identified as C. chauvoei by immunohistochemistry. Anaerobic culture and fluorescent antibody tests performed on skeletal muscle from both the dam and fetus were positive for C. chauvoei, confirming a diagnosis of blackleg. Blackleg is a so-called endogenous infection, and the currently accepted pathogenesis involves ingestion of spores that are transported to muscle tissues where they lie dormant until anaerobiosis prompts germination. Germinating bacteria are histotoxic, producing severe, local necrosis and ultimately lethal toxemia. This model, however, has not been confirmed experimentally and also fails to explain some cases of the disease. A presumptive diagnosis of blackleg is based on clinical, gross, and histologic findings. Diagnostic confirmation necessitates the detection of C. chauvoei by culture, PCR, or immunodetection methods.

Neurotropism is a striking characteristic of bornaviruses, including parrot bornavirus 2 (PaBV-2). Our study evaluated the distribution of inflammatory foci and viral nucleoprotein (N) antigen in the brain and spinal cord of 27 cockatiels ( Nymphicus hollandicus) following experimental infection with PaBV-2 by injection into the pectoral muscle. Tissue samples were taken at 12 timepoints between 5 and 114 days post-inoculation (dpi). Each experimental group had approximately 3 cockatiels per group and usually 1 negative control. Immunolabeling was first observed within the ventral horns of the thoracic spinal cord at 20 dpi and in the brain (thalamic nuclei and hindbrain) at 25 dpi. Both inflammation and viral antigen were restricted to the central core of the brain until 40 dpi. The virus then spread quickly at 60 dpi to both gray and white matter of all analyzed sections of the central nervous system (CNS). Encephalitis was most severe in the thalamus and hindbrain, while myelitis was most prominent in the gray matter and equally distributed in the cervical, thoracic, and lumbosacral spinal cord. Our results demonstrate a caudal to rostral spread of virus in the CNS following experimental inoculation of PABV-2 into the pectoral muscle, with the presence of viral antigen and inflammatory lesions first in the spinal cord and progressing to the brain.

We describe an outbreak of histomoniasis in free-range chickens ( Gallus gallus domesticus ) in the semiarid region of Paraiba State, Brazil. Juvenile chickens aged approximately 48 days showed disease over a 15-day period. Seven of 16 chickens showed yellow, watery stool, anorexia, lethargy, and death within 3-5 days of clinical illness. The mortality rate was 43.7%. The chickens were raised in a backyard with 12 adult birds that remained healthy. None of the chickens were vaccinated or dewormed. A necropsy on one deceased bird showed lesions confined to the cecum and liver. The left cecum was distended and had yellow, slightly elevated areas on the serosa. The liver was reddened with centrally depressed areas surrounded by a pale halo, which were distributed throughout the capsular surface and extended deep throughout the parenchyma. Microscopically, typhlitis and pyogranulomatous necrotizing hepatitis associated with numerous intralesional Histomonas trophozoites was observed. The birds were administered metronidazole and albendazole, which effectively controlled the histomoniasis. Although histomoniasis is rare in free-range poultry, it can occur and cause high mortality and significant economic losses.

Infections by free-living amoebae can cause systemic disease in animals and humans. We describe the epidemiological, clinical and pathological aspects of disseminated acanthamoebiasis associated with canine distemper in three dogs of the semiarid region of Paraíba, Northeastern Brazil. Affected dogs developed progressive neurological and respiratory signs that progressed to death within in two to 20 days. Gross lesions were irregular and with yellow-reddish nodules randomly distributed in the lungs, heart, kidneys, spleen, lymph nodes, adrenals, and intestine. One dog had foci of malacia in the parietal cortex and another one in nucleus of brain basis. Histologically, pyogranulomas with areas of necrosis and hemorrhage in all organs affected were observed, associated with myriads of intralesional amoebic trophozoites. All three cases were concomitant canine distemper, that possibly triggered immunosuppression in the dogs. The diagnosis was performed through microscopic findings of infection by free-living amoebae and confirmed Acanthamoeba sp. by immunohistochemistry Infecções por amebas de vida livre podem causar doença sistêmica nos animais e no homem. Descrevem-se os aspectos epidemiológicos, clínicos e patológicos de acanthamoebíase disseminada associada com cinomose em três cães na região semiárida da Paraíba, Nordeste do Brasil. Os cães afetados desenvolveram sinais respiratórios e neurológicos progressivos, que evoluíram para a morte em dois a 20 dias. Na necropsia havia áreas nodulares, irregulares e amarelo-avermelhadas distribuídas aleatoriamente em pulmões, coração, rins, fígado, baço, linfonodos, adrenal e intestino. Em um caso havia foco de malácia no córtex parietal e outro em núcleo da base encefálica. Histologicamente, foram observados piogranulomas com áreas de necrose e hemorragia em todos os órgãos afetados, associados a miríades de amebas intralesionais. Nos três casos havia cinomose concomitante, que possivelmente desencadeou imunossupressão nos cães. O diagnóstico foi realizado através dos achados microscópicos de infecção por amebas de vida livre e confirmado Acanthamoeba sp. pela imuno-histoquímica

Parrot bornaviruses (PaBVs) are the causative agents of proventricular dilatation disease, however key aspects of its pathogenesis, such as route of infection, viral spread and distribution, and target cells remain unclear. Our study aimed to track the viral spread and lesion development at 5, 10, 20, 25, 35, 40, 60, 80, 95 and 114 dpi using histopathology, immunohistochemistry, and RT-PCR. After intramuscular inoculation of parrot bornavirus 2 (PaBV-2) in the pectoral muscle of cockatiels, this virus was first detected in macrophages and lymphocytes in the inoculation site and adjacent nerves, then reached the brachial plexus, centripetally spread to the thoracic segment of the spinal cord, and subsequently invaded the other spinal segments and brain. After reaching the central nervous system (CNS), PaBV-2 centrifugally spread out the CNS to the ganglia in the gastrointestinal (GI) system, adrenal gland, heart, and kidneys. At late points of infection, PaBV-2 was not only detected in nerves and ganglia but widespread in the smooth muscle and/or scattered epithelial cells of tissues such as crop, intestines, proventriculus, kidneys, skin, and vessels. Despite the hallmark lesion of PaBVs infection being the dilation of the proventriculus, our results demonstrate PaBV-2 first targets the CNS, before migrating to peripheral tissues such as the GI system.

We describe the pathologic and immunohistochemical findings in five cases of rabies in the insectivorous Pallas's mastiff bat (Molossus molossus) in the city of Patos, state of Paraiba, northeastern Brazil. All cases were found during the day, in different neighborhoods, prostrate and unable to fly. No significant lesions were observed at necropsy or on histologic examination. The brains of the five bats showed strong immunohistochemical labeling for rabies virus in the form of large corpuscles or multiple clusters of granules within the perikarya of neurons in different areas of the brain, mainly in the cerebral cortex and cerebellar Purkinje cells. Three bats tested by direct immunofluorescence and mouse inoculation were also positive for rabies. These data demonstrate that M. molossus may be infected with the rabies virus and develop rabies, even without histologic lesions in the central nervous system, and can be a source of infection for humans and domestic animals.